Dual Nanoparticle Conjugates for Highly Sensitive and Versatile Sensing Using 19 F Magnetic Resonance Imaging

• Published in: Angewandte Chemie International Edition 2024-01, Vol.63 (4), p.e202312322
• Main Authors: Cooke, Daniel J, Maier, Esther Y, King, Tyler L, Lin, Haoding, Hendrichs, Santiago, Lee, Slade, Mafy, Noushaba N, Scott, Kathleen M, Lu, Yi, Que, Emily L
• Format: Article
• Language: English
• Subjects: Animals; Humans; Magnetic Iron Oxide Nanoparticles; Magnetic Resonance Imaging - methods; Mice; Nanoparticles - chemistry; Silicon Dioxide - chemistry; Thrombin
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202312322

Fluorine magnetic resonance imaging ( F MRI) has emerged as an attractive alternative to conventional H MRI due to enhanced specificity deriving from negligible background signal in this modality. We report a dual nanoparticle conjugate (DNC) platform as an aptamer-based sensor for use in F MRI. DNC consists of core-shell nanoparticles with a liquid perfluorocarbon core and a mesoporous silica shell ( F-MSNs), which give a robust F MR signal, and superparamagnetic iron oxide nanoparticles (SPIONs) as magnetic quenchers. Due to the strong magnetic quenching effects of SPIONs, this platform is uniquely sensitive and functions with a low concentration of SPIONs (4 equivalents) relative to F-MSNs. The probe functions as a "turn-on" sensor using target-induced dissociation of DNA aptamers. The thrombin binding aptamer was incorporated as a proof-of-concept (DNC ), and we demonstrate a significant increase in F MR signal intensity when DNC is incubated with human α-thrombin. This proof-of-concept probe is highly versatile and can be adapted to sense ATP and kanamycin as well. Importantly, DNC generates a robust F MRI "hot-spot" signal in response to thrombin in live mice, establishing this platform as a practical, versatile, and biologically relevant molecular imaging probe.